Selection of ideal candidates for extratemporal resective epilepsy surgery in a country with limited resources.

AIM: To investigate how to select ideal candidates for extratemporal resective epilepsy surgery, without compromising efficacy and safety, in countries with limited pre-surgical diagnostic facilities. METHOD: From the prospective database maintained at an epilepsy surgery centre in southern India, we reviewed the attributes of consecutive patients who had completed at least two years of follow-up after resections involving frontal, parietal and occipital lobes for medically refractory focal seizures. RESULTS: Of 386 patients diagnosed with extratemporal refractory epilepsies during the study period, 61 (15.8%) were selected based on the presence of magnetic resonance imaging (MRI)-identified lesions (in all) and concordant scalp recorded electroencephalographic (EEG) data (in nearly two thirds). Seventeen (27.8%) required invasive investigations either to define the ictal onset zone, eloquent area, or both. During a median follow-up period of five years, 63% of our patients were seizure-free, excluding the presence of auras. Permanent disabling neurological sequelae occurred in three (4.9%) patients. According to univariate analysis, pre-operative secondary generalised seizures and interictal epileptiform discharges (IEDs), during a one-year post-operative EEG monitoring period, portended unfavourable seizure outcome. In multivariate analysis, frontal lobe resections and IEDs in post-operative EEGs were independent predictors of unfavourable outcome. CONCLUSIONS: Extratemporal resective epilepsy surgery can be undertaken in countries with limited resources with efficacy and safety, comparable to that in developed countries, when patients are selected based on the presence of MRI-identified lesions and scalp EEG concordance. In such patients, invasive EEG examinations, when necessary, can be undertaken by limited coverage of cortical areas at an affordable cost.

Corpora amylacea in mesial temporal lobe epilepsy: clinico-pathological correlations.

PURPOSE: To investigate the electro-clinical significance of premature accumulation of corpora amylacea (CoA) in the resected hippocampus of patients with medically refractory mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS). METHODS: We compared the clinical and EEG characteristics, and post-operative seizure outcome of 373 (mean age 29.4 years, range 7-55 years) surgically treated MTLE-HS patients with (MTLE-HS-CoA(+), n=129 [34.5%]) and without (MTLE-HS-CoA(-), n=244 [65.5%]) CoA. RESULTS: Age at surgery was significantly higher and duration of epilepsy before surgery was significantly longer for MTLE-HS-CoA(+) patients compared to MTLE-HS-CoA(-) patients. Although the distribution of interictal epileptiform EEG abnormalities did not differ, type 1 ictal EEG pattern was more frequent in MTLE-HS-CoA(+) patients. Among the 21 patients with major interictal psychosis detected prior to epilepsy surgery, 19 (90.5%) belonged to MTLE-HS-CoA(+) group. Schizophrenia-like psychosis was most prevalent. The post-operative seizure-free outcome was comparable, but significantly more MTLE-HS-CoA(-) patients were free of antiepileptic drugs. CONCLUSIONS: Overall, our observations support the hypothesis that the pathological process in MTLE-HS is progressive. MTLE-HS-CoA(+) patients are predisposed to increased psychiatric morbidity. In vivo detection of hippocampal CoA accumulation in the future will help us to understand the neurobiological significance of this phenomenon.

Medically refractory epilepsy associated with temporal lobe ganglioglioma: characteristics and postoperative outcome.

OBJECTIVES: To define the postoperative seizure outcome and its predictors in patients with ganglioglioma-related temporal lobe epilepsy (TLE). PATIENTS AND METHODS: We reviewed the pre- and post-surgical evaluation data of 23 patients with temporal lobe ganglioglioma, who had completed >or=1 year of postoperative follow-up. They comprised 4.9% of the patients with TLE and 67.6% of the tumoral TLE operated in a developing country epilepsy center during an 8-year period. RESULTS: Median age at surgery was 20 years; median duration of epilepsy prior to surgery was 9 years. Magnetic resonance imaging (MRI) revealed tumor in mesial temporal location in 18 patients (78.3%) and in the lateral location in 2; in the remaining 3, involved both mesial and lateral regions. EEG abnormalities were localized to the side of lesion in the majority. Mesial temporal lobe structures were included in the resection, if they were involved by the tumor; otherwise, lesionectomy alone was performed. During a median follow-up of 4 years, 19 (82.6%) patients were completely seizure-free. Epileptiform abnormalities persisting in the 1-year postoperative EEG predicted unfavorable seizure outcome. CONCLUSION: We emphasize that, in patients with temporal lobe ganglioglioma, when the seizures are medically refractory, surgery offers potential for cure of epilepsy in the majority.

Electro-clinical characteristics and postoperative outcome of medically refractory tumoral temporal lobe epilepsy.

BACKGROUND: Very few studies have specifically addressed surgical treatment and outcome of patients with tumor-related temporal lobe epilepsy (TLE). AIM: To define the postoperative seizure outcome and the factors that influenced the outcome of patients with tumor-related TLE. MATERIALS AND METHODS: We selected patients whose surgical pathology revealed a temporal lobe neoplasm and who had completed > 1 year of postoperative follow-up. We reviewed the clinical, EEG, radiological and pathological data, and the seizure outcome of these patients and assessed the factors that influenced the outcome. RESULTS: Out of the 409 patients who underwent surgery for refractory TLE during the 8-year study period, there were 34 (8.3%) patients with temporal lobe neoplasms. The median age at surgery was 20 years and the median duration of epilepsy prior to surgery was 9.0 years. MRI revealed tumor in the mesial location in 21 (61.8%) patients. Interictal and ictal epileptiform EEG abnormalities were localized to the side of th lesion in the majority. Mesial temporal lobe structures were included in the resection, if they were involved by the tumor; otherwise, lesionectomy alone was performed. During a median follow-up of 4 years, 27 (79%) patients were completely seizure-free. The only factor that predicted long-term seizure-free outcome was being seizure-free during the first two postoperative years. CONCLUSIONS: Our results emphasize the fact that in patients with tumoral TLE, when the seizures are medically refractory, surgery offers potential for cure of epilepsy in the majority.